A cloned animal is produced by demecolcine treatment characterized by
culturing the nuclear transfer embryo in vitro and transferring the
embryo in vivo. This significantly improves in vitro development of
somatic cell nuclear transfer embryos and maintenance of pregnancy from
transfer of transfer somatic cell nuclear transfer embryos in a surrogate
mother up to delivery. A nuclear transfer embryo of a non-primate mammal
made by enucleating a recipient oocyte; injecting a nuclear donor cell
into the enucleated oocyte; fusing together the injected enucleated
oocyte with the injected nuclear donor cell to form a fused oocyte;
activating the fused oocyte; and treating the activated oocyte with
demecolcine to form the nuclear transfer embryo.